Broadband VPN Router User’s Manual

Options
Respond to ICMP

The ICMP protocol is used by the "ping" and "trace route" programs,

(ping)

and by network monitoring and diagnostic programs.

 

∙ If checked, VRT-311 / VRT-311S will respond to ICMP packets

 

 

received from the Internet.

 

∙ If not checked, ICMP packets from the Internet will be ignored.

 

 

Disabling this option provides a slight increase in security.

 

 

Allow VPN pass-

If enabled, PCs on the LAN can use VPN software to connect to

through

remote clients via the Internet connection. The protocols supported

 

are:

 

 

∙

IPSec

 

 

IPSec protocol is used to establish a secure connection, and is

 

 

widely used by VPN (Virtual Private Networking) programs.

 

∙

PPTP

 

 

PPTP (Point to Point Tunneling Protocol) is widely used by VPN

 

 

(Virtual Private Networking) programs.

 

∙

L2TP

 

 

L2TP is a protocol developed by Cisco for VPNs (Virtual Private

 

 

Networks).

 

 

Drop fragmented

If enabled, fragmented IP packets are discarded, forcing re-

IP packets

transmission of these packets. In some situations, this could prevent

 

successful communication.

 

Normally, this setting should be disabled.

 

 

Block TCP Flood

A TCP flood is excessively large number of TCP connection requests.

 

This is usually a DoS (Denial of Service) attack.

 

This setting should normally be enabled.

 

 

Block UDP Flood

A UDP flood is excessively large number of UDP packets. This is

 

usually a DoS (Denial of Service) attack.

 

This setting should normally be enabled.

 

 

Block non-

Abnormal packets are often used by hackers and in DoS attacks, but

standard packets

may also be generated by mis-configured network devices. (PCs will

 

normally not generate non-standard packets.)

 

This setting should normally be enabled.

 

 

 

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